Pressure tank floating diaphragm

ABSTRACT

A float, formed by two discs of flexible sheet material, diametrically substantially equal to the inside diameter of a water tank are flatly joined together inwardly of their peripheries to form a plurality of concentric annular airspaces between the discs. A length of tubing forming an endless ring is placed between the sheets of material within the outermost airspace. The float is placed within a pressure water tank and floats on the water at its interface with the air thereabove.

United States Patent [72] lnventor Harley L. West 720 Kingston Drive, Yukon, Okla. 73099 [21 Appl. No. 852,440 [22] Filed Aug. 22, 1969 [45] Patented Jan. 26, 1971 Continuation-impart of application Ser. No. 691,420, Dec. 18, 1967, now abandoned.

[54] PRESSURE TANK FLOATING DIAPHRAGM 2 Claims, 7 Drawing Figs.

[52] US. Cl 220/26 [51] Int. Cl B65d 87/18 [50] Field of Search 277/226;

[56] References Cited UNITED STATES PATENTS 3,159,301 12/1964 Anderson 3,357,591 12/1967 David 3,366,266 1/ 1968 Heartstedt Primary Examiner-William F. ODea Assistant Examiner-Robert 1. Smith Attorney-Robert K. Rhea ABSTRACT: A float, formed by two discs of flexible sheet material, diametrically substantially equal to the inside diameter of a water tank are flatly joined together inwardly of their peripheries to form a plurality of concentric annular airspaces between the discs. A length of tubing forming an endless ring is placed between the sheets of material within the outermost airspace. The float is placed within a pressure water tank and floats on the water at its interface with the air thereabove.

PATENTEnJAuzslsn 3557994 Ill/IZLL IIlI/II/IV/II IIIIIlIIIIIIII/I/[llIIll/l/III -IYIIIIIIIII HAR LEY L. WEST INVEN TOP.

PRESSURE TANK FLOATING DIAPHRAGM CROSS-REFERENCE TO APPLICATION This invention is a continuation-in-part of an application flled by me in the US. Patent Ofiice Dec. 18, 1967, Ser. No. 691,420, and now abandoned, for PRESSURE TANK FLOATING DIAPHRAGM.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to pressure water systems and more particularly to a disclike floating diaphragm to be interposed between water within a tank and air under pressure thereabove.

Pressure water systems normally use a reservoir or supply tank containing air under pressure which acts directly upon the water to place the latter under a desired pressure. Where air, under pressure is used, air volume controls and pumps are usually necessary in addition to the water pump. One type of water pressure system presently in use employs a tank containing a desired volume of air wherein the water is pumped into the depending end of the tank and as its level rises the air is compressed in the upper portion of the tank. In this type of installation it is desirable to provide a means for maintaining an interface between the water and the air to more effectively use the compressed air against the water contained by the tank. Various types of floats, such as circular sections of sponge material or tube members, have been used for this purpose but these devices, for the most part have proved unsatisfactory for the reason that they become waterlogged and sink. The desired result is accomplished by a float ring or diaphragm formed of sheet material having a greater density than the air and less density than water. Variations of tank sizes or inside dimensions are compensated for by this invention which employs a length of tubing which is not joined at its respective ends but is telescopingly connected and is free to expand in a circular fashion under its inherent resiliency, after being placed within the tank to occupy the diametric limit of a concentric airspace formed between the sheets of material forming the diaphragm.

2. Description of the Prior Art The most pertinent prior art patents of which I am aware are the U.S. Pats. to Wade et al., No. 3,049,261; Anderson, No. 3,159,301; and David, No. 3,357,591. The sheet material forming the floats of these patents are sealed together at their peripheral edges whereas this invention discloses unsealed separable peripheral edge portions of the sheets forming the float so that the respective peripheral edge portion of each sheet remains more flexible to readily conform to variations in tank size and ride or slide over obstructions, such as corrosion, rust or other irregularities, on the inner wall surfaces of a water tank.

SUMMARY OF THE INVENTION The floating diaphragm is formed from two discs of flexible waterproof sheet material, having a diameter substantially equal to the inside of a water tank, which are sealed together along concentric radially spaced-apart lines inwardly of their peripheries forming concentric airspaces or chambers, the outermost one of which receives a length of flexible tubing having a length greater than the outer limit or circumferences of this chamber. The ends of the tube are telescopingly engaged. The assembled diaphragm is inserted into a water tank through a water inlet opening by diametrically doubling or folding the diaphragm upon itself so that it may be inserted through the water inlet opening. The resiliency of the flexible tube tending to flex outwardly within the chamber telescopically expands the tube ends and extends the diaphragm to a disclike shape which floats at the surface of water pumped into the tank. The free unsealed peripheral edge portions of the sheets resiliently engage the inner wall surface of the tank. Air trapped above the diaphragm in turn exerts pressure against the water.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical cross-sectional view of a pressure water tank having the diaphragm, shown in elevation, installed therein;

FIG. 2 is a perspective view, to a larger scale, of the diaphragm, per se;

FIG. 3 is a plan view of the telescopingly joined flexible tube;

FIG. 4 is a fragmentary vertical cross-sectional view, to a larger scale, taken substantially along the line 4-4 of FIG. 2;

FIG. 5 is a perspective view of the diaphragm when folded toward a tank installing position;

FIG. 6 is a fragmentary vertical cross-sectional view of the diaphragm contacting the tank wall; and

FIG. 7 is a fragmentary sectional view illustrating apparatus utilized in assembly of the components.

DESCRIPTION OF THE PREFERRED EMBODIMENT Like characters of reference designate like parts in those figures of the drawings in which they occur.

In the drawings:

The reference numeral 10 indicates a water tank comprising an upright cylinder which communicates, at its bottom end portion, with a suitable water inlet or flow line 12 connected with an inlet opening 14 in the tank. The flow line 12 receives water from a source of supply by pumping equipment, not shown, so that water 16 may accumulate in the tank and be dispensed from the tank through an outlet 18 adjacent the bottom of the tank.

The numeral 20 indicates the diaphragm which floats on the water 16 and places the latter under pressure by air within the upper end portion of the tank 10. The diaphragm 20 is preferably formed from flexible plastic sheet material impervious to water and comprises opposing diametrically equal discs 22 and 24. Diametrically the discs 22 and 24 are preferably equal to or slightly greater than the inside diameter of the tank 10. The discs 22 and 24 are positioned one above the other with their perimeters coinciding and are heat sealed or bonded together forming a concentric relatively narrow, approximately %l-II'ICII wide, circumferentially bonded outer path 26 radially spaced inwardly of their perimeters and defining free marginal edge portions or lips 23 and 25 for the respective discs 22 and 24.

Prior to fon'ning the sealed path 26 a length of flexible tubing, indicated at 32, is placed between the discs 22 and 24. The tubing 32 is preferably a length of plastic or other similar material having one end portion diametrically enlarged, as at 34, so that its inside diameter freely receives the other end portion of the tubing in telescoping relation. Straight tubing is preferred so that the inherent resiliency of the tube, when deformed to describe a circle, tends to cause its telescoped ends to separate.

Concentrically spaced inwardly of the tube 32, the discs 22 and 24 are again bonded or heat sealed together to form an intennediate relatively narrow path 36 to define an annular chamber 38 containing the tube 32 which is substantially greater in cross section area than the cross section area of the contained tube 32. Radially spaced inwardly of the path 36 the central area of the discs 22 and 24 are then heat sealed or bonded to form an inner sealed path 40 thus defining an intermediate chamber 42 and a central chamber 44. The purpose of the inner chamber 44, in addition to providing airspace for adding to the buoyancy of the diaphragm, is to permit greater flexibility for installing the device as presently explained.

The radial spacing between the outer sealed path 26 and the perimeter of the discs 22 and 24 is preferably substantially greater than the cross section area of the tube 32. The purpose of the free disc edge portions or lips 23 and 25 is to permit greater flexibility and a wiping action on the tank wall of these marginal edge portions of the diaphragm than is possible if these marginal edges are bonded together either throughout their transverse width or only adjacent their circumferential edges. These free edge portions or lips 23 and 25 compensate for irregularities such as calcium deposits or rust on the inner wall surface of the tank.

As illustrated in FIG. 7, the discs 22 and 24 may be heat sealed along the respective paths 26, 36 and 40 by interposing them between cooperating opposed concentric dies comprising two opposing sets of three cylindrical wall members 26A, 36A and 40A secured in opposing platens 50 and 52. The dies are heated and moved toward each other with the components forming the float 20 disposed therebetween OPERATION In operation the water inlet line 12 is disconnected from the tank when the latter is emptied of water and the assembled diaphragm 20 is diametrically folded to the position shown by FIG. 5, wherein the diametric fold line extends across the tubing 32 at a point remote from the telescoping sleeve section 34. Pressure is then manually applied at points 45 and 46 of the folded diaphragm to define a substantially crescent shape so that one of its ends may then be forced through the tank inlet opening l4. After the diaphragm has been manually inserted through the opening 14 the resiliency of the tube 32, flexing outwardly, against the outer limit of the chamber 38 results in the diaphragm assuming a disclike configuration. The waterline 12 is again connected'and the water 16 is introduced into the tank to a desired level wherein the diaphragm 20 floats on the upper surface of the water and provides, by its peripheral edges or lips 23 and 25, contacting the inner wall of the tank, a seal between the water and air trapped in the tank thereabove. As mentioned hereinabove the outermost marginal edge portions or lips 23 and 25 permits a flexing of the peripheral edges of the diaphragm so that they perform a wiping action on the inner wall of the tank and will permit upward passage of air or downward passage of water with respect to the float 20. The air trapped in the tube 32 and in its surrounding annular chamber 38 is sufficient to insure that the diaphragm is maintained in floating relation so that it will move vertically with the rise and fall of water within the tank as the latter is used or replaced. However, I have found that, occasionally while installing one of the floats in a tank, one or the other of the discs 22 or 24 will be ruptured forming the ring-containing chamber 38 which is usually caused by a bur or sharp thread on the wall defining the tank opening through which the float is being forced. This is usually a relatively small opening or cut through the damaged disc but results in water entering and gradually filling or at least partially filling the chamber containing the ring which causes the float to float low in the water rather than at its interface with the air thereabove thus reducing its efficiency. The additional buoyancy provided by the chambers 42 and 44 will support the diaphragm in the event one of the discs are ruptured in that area forming the chamber 38. Furthermore, the provision of the three chambers 38, 42 and 44 tends to prevent a folding action of the float and its being forced into and through the water outlet opening 18 by air pressure in the tank in the event the water level is lowered to or near the level ofthe opening 18.

Obviously the invention is susceptible to some changes or alteration without defeating its practicability, and I therefore do not wish to be confined to the preferred embodiment shown in the drawings and described herein.

lclaim: l. A floating diaphragm for pressure water tank having an inner wall, comprising:

a pair of superposed discs formed from flexible resilient material; a flexible and resilient tube concentrically interposed between said discs; and bonding means joining said discs together to form outer, in-

termediate and inner concentric radially spaced-apart paths radially spaced inwardly of their marginal edge portions; said outer and intermediate paths forming an outer annular air chamber surrounding said tube; said inner path forming a central air chamber and an intermediate annular air chamber; and said discs projecting outwardly beyond the outer path and forming a pair of flexible lips resiliently engaging the inner wall of said tank.

2. Structure as specified in claim 1 in which the length of said tube is greater than the greatest circumferential limit of said outer annular air chamber;

one end of said tube being diametrically enlarged a longitudinal distance substantially greater than its diameter for telescopingly receiving its other end portion in sliding relation; and

said tube being capable of being diametrically folded with said discs and inserted into said tank through an opening therein. 

1. A floating diaphragm for pressure water tank having an inner wall, comprising: a pair of superposed discs formed from flexible resilient material; a flexible and resilient tube concentrically interposed between said discs; and bonding means joining said discs together to form outer, intermediate and inner concentric radially spaced-apart paths radially spaced inwardly of their marginal edge portions; said outer and intermediate paths forming an outer annular air chamber surrounding said tube; said inner path forming a central air chamber and an intermediate annular air chamber; and said discs projecting outwardly beyond the outer path and forming a pair of flexible lips resiliently engaging the inner wall of said tank.
 2. Structure as specified in claim 1 in which the length of said tube is greater than the greatest circumferential limit of said outer annular air chamber; one end of said tube being diametrically enlarged a longitudinal distance substantially greater than its diameter for telescopingly receiving its other end portion in sliding relation; and said tube being capable of being diametrically folded with said discs and inserted into said tank through an opening therein. 